Method and device for charging coke ovens with compacted coal by use of a charging plate separator layer

ABSTRACT

Disclosed is a method and device for charging the chambers of a coke oven with compacted coal. The method includes placing a plurality of adhesion reduction particles onto a coke oven charging plate, the particles being configured to reduce at least one of adhesion forces and friction forces present between the charging plate and compacted coal to be loaded thereon, loading compacted coal onto the charging plate, moving the charging plate loaded with compacted coal to the coke oven chamber, and slidably removing the compacted coal from the charging plate such that the compacted coal is disposed in the coke oven chamber. The device comprises a metal plate configured to load compacted coal into the coke oven, a plurality of adhesion reduction particles affixed to the metal plate by an adhesive layer, and a device used to move the metal plate to a front of the firing chamber of the coke oven.

The invention relates to a method for charging coke-oven chambers of the heat-recovery or non-recovery type, by which coke-oven chambers are loaded by means of a charging plate which is moved towards the coke-oven chambers for charging them, and the charging plate is provided with stacked compressed blocks of coal or with a ready compressed coal cake before charging the coke-oven chambers and moved towards the coke-oven chambers for charging, and the coke-oven chambers are loaded by pulling the charging plate out of the coke-oven chamber at the front or by means of a pusher head, with the charging plate being provided with a layer of particles before being loaded with coal to reduce the adhesive forces so that the compressed coal cake or the coal compacts do not adhere on the charging plate. The invention further relates to a device comprising a charging plate which is provided with an adhesive layer of particles reducing the adhesive forces.

Coke ovens of the heat-recovery or non-recovery type carbonise the coal in coke-oven chambers which have a gas space above the coal cake depending on the load, this space being referred to as primary heating space into which the coking gases escape and where they are partially combusted. Examples of coke ovens of this type are described in patent specifications U.S. Pat. No. 4,344,820A, U.S. Pat. No. 4,287,024A, U.S. Pat. No. 5,114,542A, GB1555400A or CA2052177C. The partially combusted coking gas is then passed into so-called secondary heating spaces which are located below the coke-oven chambers and in which the partially combusted coking gas from the primary heating space is combusted completely. These consecutive combustion steps serve to heat the coal cake evenly from the top and from the bottom during the coking process.

Coke-oven chambers which are not of the heat-recovery or non-recovery type collect the coking gas for subsequent processing and use a foreign gas for heating. Such coke ovens are called conventional coke-oven chambers. Coke ovens of this kind are described, for example, in patent specification U.S. Pat. No. 3,972,780A. The dimensions of coke ovens of the heat-recovery or non-recovery type are different from conventional coke-oven chambers as a result of the aforementioned method of consecutive combustion steps. For this purpose, coke-oven chambers of the heat-recovery or non-recovery type are normally loaded through the coke-oven chambers at the front prior to the coking operation.

To simplify and rationalise charging of the coke-oven chambers, there are state-of-the-art methods according to which the coal is compressed to compacts prior to loading, these ready compacts then being loaded into the coke-oven chambers. A related exemplary embodiment is described in DE415846C or DE102009012453A1. Another possibility is to provide a compressed coal cake which is of about the same dimensions as the coke-oven chamber to be loaded and to load it into the coke-oven chamber, It is also possible to compress the coal to compacts directly on a charging plate and to implement loading straight from the charging plate. A related exemplary embodiment is described in WO2011057721A2.

After the compressed coal cake or the coal compacts have been provided, actual charging of the coke-oven chamber is implemented. DE 19545736 A1 describes a method for charging a coke oven which is bottom-heated and provided with low charging height and large oven sole area, with the coal being loaded into the coke-oven chamber in horizontal direction and a compressed coal cake being pushed into the oven chamber on the base plate of a charging car and the base plate being pulled out of the coke-oven chamber while holding on to the coal cake at the front end. In this way the coke-oven chamber is loaded with a compressed coal cake. The base plate of such a charging car is also referred to as charging plate as it is used to bear the readily compacted compressed coal cake prior to loading.

Loading involves the problem that it is required to park the charging car in the vicinity of the coke-oven chambers for extended periods of time. As a result, the car heats up. In the course of the charging process, the charging plate usually also rests fully upon the hot coke-oven sole to the effect that it heats up even further. As a result, the boundary layer of the coal load on the charging plate adopts the temperature of the latter. This will make the tarry coking products degas, leading to the formation of an adhesion layer between the charging plate and the compressed coal cake. This layer makes the coal cake or the ready coal compacts adhere on the charging plate, which is not desired in view of subsequent processing and loading.

The formation of an adhesion layer will strongly intensify the friction between coal cake and charging plate, causing deformation of the coal cake resting on the charging plate when the latter is pulled out. This may, for example, make the side edges of the coal cake break off when the coal cake is charged into the coke-oven chambers so that not insignificant parts of the coal cake fall off the charging plate. This involves an undesired loss of coal during the loading process. It may also happen that parts of the coal cake broken off the side edges pile up in the loading process, leading to uneven loading of the coal cake into the coke-oven chambers. This will as a consequence reduce the performance of the coke-oven chamber concerned.

It is therefore the aim to provide a method to prevent or at least lessen the formation of an adhesion layer between the coke-oven chamber and the charging plate so to prevent undesirable breaking off of parts of the coal cake when the coal cake is being loaded.

The invention achieves this aim by putting particles on the charging plate, these particles being applied prior to placing the coal cake on the charging plate so that these form a separating layer between coal cake and charging plate. The charging plate may either be part of a coal charging machine or a separate plate used to bear a coal cake. The particles are temperature-resistant fines which are resistant to high temperatures in the environment of coke-oven chambers and are of no or only very little effect on the carbonisation of the coal cake.

Claim is especially laid on a method for charging coke-oven chambers of the heat-recovery or non-recovery type with compacted coal on a charging-plate separating layer, by which

-   -   the coal is provided in compacted form as stacked compressed         blocks or as a compressed coal cake, and     -   the coal is loaded in this compacted form onto a charging plate         which is used for approaching the coke-oven chamber to be         charged and from which, after having approached the coke-oven         chamber, the compacted coal is pushed into the coke-oven         chamber, or     -   a charging plate with suitable compressing and enclosing devices         is provided with coal so to form a compression mould, from which         one or more compressed coal cakes are made available by         compression on the charging plate, and the latter being pushed         into the coke-oven chamber upon entry,

and which is characterised in that

-   -   particles are scattered over the charging plate before loading         it with coal, the particles achieving a reduction of the         adhesive forces between coal cake and charging plate.

Loading itself may, for example, be carried out by pulling the charging plate with the coal compacts or the compressed cake out of the coke-oven chamber at the front, it may also be done by a pusher head, for example. Loading itself may also be carried out by entry of the charging plate into the coke-oven chamber to be charged, and from which the compacted coal can be pushed into the coke-oven chamber after having approached the coke-oven chamber with the charging plate, and the charging plate is pulled out of the coke-oven chamber.

In an embodiment of the invention, the particles are sand. The latter is adequately stable towards the temperatures to be expected of the charging plate and reduces the adhesion between the coal cake and the charging plate to a sufficient degree. In another embodiment, fine coke is used as particles. It may be produced in any way desired. In a further embodiment, the particles are ash. The ash may also be produced in any way desired. All particles can be of any grain size or grain size distribution.

In a further embodiment, the particles are mixed from the components sand, fine coke, or ash or at least from two of these components.

The particles are put on the charging plate in any way desired. In a simple embodiment of the invention, they are scattered over the charging plate. The particles can be scattered over the charging plate immediately before use but can also be scattered over the plate and then kept ready until use in a safe place of the coke-oven battery. The particles may also be fixed on the charging plate. This can, for example, be implemented by an adhesive layer. The latter can, for example, be made of tar which is mixed in an adequate amount with the particles, after which the mixture obtained is spread onto the charging plate.

Claim is also laid on a metal plate as charging plate for loading coke-oven chambers with a compressed coal cake or with coal compacts, comprising

-   -   a metal plate used to load the compressed coal cake or the coal         compacts, and     -   a device used to move or transport the metal plate along the         coke-oven chamber front,

and which is characterised in that

-   -   the metal plate is provided with particles via an adhesive         layer, which have the effect of reducing the adhesive forces.

For the formation of this separating layer, it is possible to use any type of particles. These particles can be sand, for example. They can also be fine coke or ash or a mixture thereof. In an embodiment of the coated metal plate, the particles are fine coke and the adhesive layer is tar. The metal plate may be available as such but it may also be part of a charging machine. This metal plate may be made available immediately before the loading process but it may also be prepared and stored until being used.

The invention is used for loading coke ovens of the heat-recovery or non-recovery type. However, it may also be used for any other type of coke ovens, provided these are suited by their dimensions for being loaded with a compressed coal cake or with coal compacts.

The invention involves the advantage of preventing coal to be carbonised from adhering to the charging plate of a charging machine for coke ovens. This allows proper loading of coke-oven chambers ensuring that no component parts of the coal cake break off or pile up unwantedly. 

1.-9. (canceled)
 10. A method for charging the chambers of a coke oven with compacted coal, comprising: placing a plurality of adhesion reduction particles onto a coke oven charging plate configured to charge the coke oven with compacted coal, the adhesion reduction particles being configured to form a separating layer between the charging plate and the compacted coal to be disposed thereon so as to reduce at least one of adhesion forces and friction forces present between the charging plate and compacted coal, so as to reduce the force required to slidably remove the compacted coal from the charging plate; loading compacted coal onto the charging plate, the compacted coal having the form of at least one of (1) a plurality of stacked compressed blocks of coal or (2) a compressed coal cake; moving the charging plate loaded with compacted coal to the coke oven chamber; and slidably removing the compacted coal from the charging plate such that the compacted coal is disposed in the coke oven chamber.
 11. The method of claim 10, further comprising: compression molding coal directly on the charging plate to form compacted coal;
 12. The method of claim 10, wherein said slidably removing the compacted coal from the charging plate is accomplished by at least one of pushing the compacted coal off of the charging plate and into the coke oven chamber, or pulling the charging plate laterally out from under the compacted coal disposed within the coke oven chamber.
 13. The method of claim 10, wherein the plurality of adhesion reduction particles are sand.
 14. The method of claim 10, wherein the plurality of adhesion reduction particles are fine coke.
 15. The method of claim 10, wherein the plurality of adhesion reduction particles are ash.
 16. The method of claim 10, wherein the plurality of adhesion reduction particles include at least one of sand, fine coke, and ash.
 17. The method of claim 10, wherein the plurality of adhesion reduction particles are scattered across an upper surface of the charging plate.
 18. The method of claim 10, wherein the plurality of adhesion reduction particles are affixed to the charging plate by means of an adhesive layer.
 19. A charging plate for loading a firing chamber of a coke oven with compacted coal, comprising: a metal plate configured to load compacted coal into the firing chamber of the coke oven; a plurality of adhesion reduction particles affixed to said metal plate by an adhesive layer, said particles being configured to reduce adhesion forces between said metal plate and compacted coal to be disposed thereon; and a device used to move the metal plate along a front of the firing chamber of the coke oven.
 20. The charging plate of claim 19, wherein said plurality of adhesion reduction particles are fine coke, and the adhesive layer is tar. 